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P0171 Diagnostic Trouble Code Discussion for March 2009

Fuel System Lean (Bank 1)


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Trouble Ticket Help Requests for DTC P0171
Help Request Posted
2001 Mercury Sable LS Premium 3.0L Poor Idle Quality, Hesitation, Surge, Stall, Misfire, MIL Lamp on VIN: 1MEHM55S41
P0171: lean. This car barely runs when cold,wont idle, surges at idle. first off sets missfire code on 1 and 3. After it warms up a bit it will set the lean codes, after it has warmed up the car runs great and idles smoothly. I swear i hear a vacum leak but on checking mos...
March 02, 2009
2004 GMC Sierra 1500 SLE 4.3L MIL Lamp on VIN: 1GTEC14X04
P0171: Fuel Trim System Lean (Bank 1). car was towed in for a no start engine was flooded with fuel replaced plugs and truck started up ran a little rough so we replaced cap and rotor wires and was running ok after running for 15 min. check engine light came on checked codes po171 there were no cod...
March 04, 2009
1998 Honda Civic LX 1.6L MIL Lamp on VIN: 2HGEJ6670W
P0171: Fuel System Too Lean. ... replaced the manifold/converter assy. due to cracks and noise. We replaced it with a Dorman aftermarket unit due to price. Ever since then we have a re-occuring p0171 lean code. We have replaced the upstream 0xygen sensor, replaced the fuel filter, the pcv...
March 04, 2009
2004 Mazda MPV LX 3.0L Poor Idle Quality, MIL Lamp on VIN: JM3LW28A14
P0171: Adaptive Fuel Trim Too Lean (Bank 1). car surges at idle. mil on after 2 days. seems like fan control module is going out (causes fan to fluctuate erratically) using a Solis the o2 sensors are doing nothing. Autozone sold customer new o2 sensors. I am a VW Audi tech and it has been a long time sin...
March 04, 2009
2001 Ford Ranger XL 2.5L MIL Lamp on VIN: 1FTYR10C11
P0171: lean mixture. After all previously listed work and lots of time spent looking at data stream and tech bulletins, this truck will still set code and engine light after a few days driving. It runs ok but trim numbers show that it wants more fuel both at idle and driving. this...
March 06, 2009
2000 Infiniti I30 3.0L MIL Lamp on, Performance=ok VIN: JNKCA31A8Y
P0171: Fuel Trim Lean (Bank 1). P0171 code on and will re-illuminate after clearing. I shot carb cleaner all around the air intake. Checking fuel trims reveals the following: STFT Bank1 & Bank2 stay on or around +- 9%. ( varies ) STFT B2 Sensor 2 stays at 99.2 all the time. Is this trul...
March 09, 2009
2001 Lexus RX300 3.0L MIL Lamp on VIN: JTJGF10U21
P0171: Lean Bank 1. ... while highway driving. P0171 and P0174. All checks ok now including + 5-10% fuel trims at 70 MPH. Both occasions, IAT was cold: 0 degrees F and 16 degrees F. There are no drivability concerns.
March 09, 2009
1999 Ford F-250 Super Duty XL 6.8L MIL Lamp on VIN: 1FTX21L3XE
P0171: bank one lean. I have smoke tested twice, check fuel pressure ok, checked pcv hose to back of intake tested mass air flow sensor according to bulletin, checks ok, will a bad MAF cause only po171 lean code, freeze frame is 1105 rpm, calc load 41.1%, coolant 204 degrees F, st ...
March 10, 2009
1999 Ford F-250 Super Duty XL 6.8L MIL Lamp on VIN: 1FTX21L3XE
P0171: bank one lean. I have smoke tested twice, check fuel pressure ok, checked pcv hose to back of intake tested mass air flow sensor according to bulletin, checks ok, will a bad MAF cause only po171 lean code, freeze frame is 1105 rpm, calc load 41.1%, coolant 204 degrees F, st ...
March 11, 2009
1999 Toyota 4Runner SR5 3.4L Hesitation, Misfire, MIL Lamp on VIN: JT3HN86R9X
P0171: Fuel System Too Lean (Bank 1). Hello there I have this 4 Runner with what seems to be a simple misfire issue. I have check plugs wires and coils and it still will misfire especially on #3. I have switched plugs wires and coils around and it still has a problem. It also has a no power when a...
March 11, 2009
2001 Toyota Corolla CE 1.8L Hesitation, Misfire, MIL Lamp on VIN: 1NXBR12E91
P0171: Fuel System Too Lean (Bank 1). ... shop with a p0171 .and p0300. My mastertech scaner shows at idle MAF 2.5 GR/s , both o2 sensors 0.00v ,stft 19%,ltft 29%. I have run fuel press ,compression,check for vac leaks and check injector resistance everything is i...
March 11, 2009
1996 Ford Taurus LX 3.0L MIL Lamp on VIN: 1FALP53S3T
P0171: system too lean bank 1. ... engine light on and 2 codes (P0171 & P0174) fuel trims Long Term were about 16% & 18%. Hooked up smoke machine and found 2 leaks, (one out of EGR gasket & other coming out of hose going to EVAP.) Fixed both of them and trim dropped down to abou...
March 12, 2009
2000 Ford Escort LX 2.0L MIL Lamp on VIN: 3FAFP13P41
P0171: lean bank1 code. ... ther driveability concerns. No stalling, poor idling or running. Fuel pressure ok, smoked for leaks at intake, checked for vac leak sources, none found. LTFT 25 at idle- normal operating temp. within normal range cold @idle. The P0731 code is intermittent....
March 12, 2009
1998 Oldsmobile Intrigue GL 3.8L MIL Lamp on VIN: 1G3WS52K3W
P0171: Fuel System Lean. THANKS IN ADVANCE I was blessed with this return work from another shop They had replaced lower intake gasket and upper intake manifild due to coolant leak Found lower intake bolts not properly torqued. removed upper and lower intake and replaced gaskets The v...
March 12, 2009
2003 Ford Windstar LX 3.8L MIL Lamp on VIN: 2FMZA50433
P0171: lean condition on bank 1. ... Ford windstar that keeps setting c.e. light with lean codes: p0171 and p0174= lean condition on both banks. We have done whatever necessary to pintpoint the source or cause of lean codes; but witout success. We have checked ...
March 13, 2009
2001 Toyota Corolla CE 1.8L Hesitation, Misfire, MIL Lamp on VIN: 1NXBR12E91
P0171: Fuel System Too Lean (Bank 1). ... shop with a p0171 .and p0300. My mastertech scaner shows at idle MAF 2.5 GR/s , both o2 sensors 0.00v ,stft 19%,ltft 29%. I have run fuel press ,compression,check for vac leaks and check injector resistance everything is i...
March 13, 2009
2002 Chevrolet Camaro 3.8L MIL Lamp on VIN: 2G1FP22K92
P0171: Fuel Trim System Lean (Bank 1). stB1-(+2%) ltB1-(+20%) stB2-(+5%) ltB2-(+20%) Couldn't locate any external vacuum leaks. There is a TSB on that condition about clogged injectors.
March 14, 2009
1999 Ford Contour SE 2.5L MIL Lamp on VIN: 1FAFP66L6X
Does anyone know if I can obtain the seals where the intake manifold runner control shaft goes into the lower intake manifold. I have a vacuum leak at these seals and the dealer says I have to buy the complete lower intake manifold assy. This is the shaft , on...
March 18, 2009
2002 Toyota Camry SE 2.4L Excessive Emissions, Misfire, MIL Lamp on VIN: 1GCCS1442T
P0171: Fuel System Too Lean (Bank 1). not to much exp on toyota 1 month ago customer brings in car has po442 decined looking into code,car run ok,now problem with idel and shows slight misfire,lean bk 1,dont know toyota to well,and would like to know what direction to take from you guys,fuel press...
March 20, 2009
2001 Volkswagen Golf GLS 2.0L MIL Lamp on VIN: 9BWGT21J61
P0171: bank 1 lean. ... repeat cust. for this concern.mil on p0171 code for bank 1 lean. cannot find vacuum lek. o2 sensors switch properly.light will shut off for few days then returns. inspected secondary air system.seems fine.sometimes will run rough in morning at first start ...
March 20, 2009
2001 Honda Accord EX 2.3L MIL Lamp on VIN: JHMCG665XX
P0171: Fuel System Too Lean (Bank 1). ... driveability symptoms. P1071 was a current code when vehicle came in and was initially tested, now has become a history code after a few road tests and a collision at the shop today. Dented fenders aside, fuel trim, ST 10-25%, LT 14-18%. Idle quality is go...
March 23, 2009
2003 Kia Spectra 1.8L No Start, Poor Idle Quality VIN: KNAFB12193
P0171: Fuel System Too Lean (Bank 1). cust complaint of dies driving and hard to restart and hard start after fueling road tested for dying did not duplicate problem customer says hard to start after every fill up i took vehicle to gas station and added fuel vehicle spins over will not start hold ...
March 23, 2009
2002 Toyota Camry SE 2.4L Excessive Emissions, Misfire, MIL Lamp on VIN: 1GCCS1442T
P0171: Fuel System Too Lean (Bank 1). not to much exp on toyota 1 month ago customer brings in car has po442 decined looking into code,car run ok,now problem with idel and shows slight misfire,lean bk 1,dont know toyota to well,and would like to know what direction to take from you guys,fuel press...
March 24, 2009
2005 Saturn Ion-1 2.2L lack of power VIN: 1G8AF54F15
P0171: Fuel System Lean. ... power. Customer stated that the car would idle good but bog down when the accelerator was pressed, and didn't have enough power to pull itself. Scanned and found the codes listed. I took it out for a test drive and the car ran perfect. Cleared codes and re...
March 25, 2009
2004 Volvo S60 2.4 2.4L Poor Idle Quality VIN: YV1RS61T64
P0171: lean mixture bank 1. Car came in with rolling idle, ck engine light, and whistling noise around #2 cyl on intake. Changed intake gskt. bolt torque was not even, but gskt looked ok. I am wondering if it is possible for the crankcase vent system to be at fault. If I pull the dipstic...
March 25, 2009
1999 Toyota Camry CE 2.2L Poor Idle Quality, Hesitation, Cuts out VIN: 4T1BG22K0X
P0171: Fuel System Too Lean (Bank 1). ... left B pillar.Disconnected battery, performed body repairs, hooked battery up no start. Checked plugs ( dry plugs ), checked spark ( good spark ), checked injector pulse ( good pulse ), checked fuel pump pressure ( only 8psi ), replaced fuel pump, engine s...
March 26, 2009
2001 Dodge Durango SLT 4.7L Poor Fuel Economy VIN: 1B4HS28N11
P0171: Fuel System Lean (Bank 1). this car has poor fuel mileage and blow black smoke at idle. i replaced upsteam and down stream and found power steering fluid in connectors and then looked and found power steering sensor leaking fluid. i replaced power steering sensor and clean all connector...
March 27, 2009
1999 Dodge Caravan SE 3.3L Excessive Emissions, MIL Lamp on, crank no start VIN: 2B4GP52G8X
P0171: Fuel System Lean (Bank 1). Here is the scoop on this caravan...At times on cold start the car will crank no start, at this time it has spark but will crank over and smells strong of fuel. The only way to get it to start is to hold your foot to the floor then of course it will run rough ...
March 29, 2009
1999 Buick Regal LS 3.8L Poor Fuel Economy, MIL Lamp on VIN: 2G4WB52K3X
P0171: Fuel System Lean. ... Initially it had a code for a mass air flow sensor code. Upon inspection of the sensor data it showed that the sensor was reading 3.88 gm/s at idle which is off from the minimum of 4 gm/s. Sensor was replaced and vehicle was fine for about 3 days. Code ret...
March 30, 2009
2005 Mercedes-Benz SLK350 3.5L Misfire VIN: WDBWK56F75
P0171: rt. bank mixture at limit at idle. Thanks as always fellow technicians Mil is on, all misfire codes and mixture codes for rt. bank of cylinders, If this was a M112 or M113 I'd be sending him to the dealer for warranty catalyst replacement on the rt. bank. I have only worked on a few of the M272...
March 30, 2009
2005 Mercedes-Benz SLK350 3.5L Misfire VIN: WDBWK56F75
P0171: rt. bank mixture at limit at idle. Thanks as always fellow technicians Mil is on, all misfire codes and mixture codes for rt. bank of cylinders, If this was a M112 or M113 I'd be sending him to the dealer for warranty catalyst replacement on the rt. bank. I have only worked on a few of the M272...
March 31, 2009
2001 Mercury Sable LS Premium 3.0L Poor Idle Quality, Hesitation, Surge, Stall, Misfire, MIL Lamp on VIN: 1MEHM55S41
P0171: lean. This car barely runs when cold,wont idle, surges at idle. first off sets missfire code on 1 and 3. After it warms up a bit it will set the lean codes, after it has warmed up the car runs great and idles smoothly. I swear i hear a vacum leak but on checking mos...
March 02, 2009
2004 GMC Sierra 1500 SLE 4.3L MIL Lamp on VIN: 1GTEC14X04
P0171: Fuel Trim System Lean (Bank 1). car was towed in for a no start engine was flooded with fuel replaced plugs and truck started up ran a little rough so we replaced cap and rotor wires and was running ok after running for 15 min. check engine light came on checked codes po171 there were no cod...
March 04, 2009
1998 Honda Civic LX 1.6L MIL Lamp on VIN: 2HGEJ6670W
P0171: Fuel System Too Lean. ... replaced the manifold/converter assy. due to cracks and noise. We replaced it with a Dorman aftermarket unit due to price. Ever since then we have a re-occuring p0171 lean code. We have replaced the upstream 0xygen sensor, replaced the fuel filter, the pcv...
March 04, 2009
2004 Mazda MPV LX 3.0L Poor Idle Quality, MIL Lamp on VIN: JM3LW28A14
P0171: Adaptive Fuel Trim Too Lean (Bank 1). car surges at idle. mil on after 2 days. seems like fan control module is going out (causes fan to fluctuate erratically) using a Solis the o2 sensors are doing nothing. Autozone sold customer new o2 sensors. I am a VW Audi tech and it has been a long time sin...
March 04, 2009
2001 Ford Ranger XL 2.5L MIL Lamp on VIN: 1FTYR10C11
P0171: lean mixture. After all previously listed work and lots of time spent looking at data stream and tech bulletins, this truck will still set code and engine light after a few days driving. It runs ok but trim numbers show that it wants more fuel both at idle and driving. this...
March 06, 2009
2000 Infiniti I30 3.0L MIL Lamp on, Performance=ok VIN: JNKCA31A8Y
P0171: Fuel Trim Lean (Bank 1). P0171 code on and will re-illuminate after clearing. I shot carb cleaner all around the air intake. Checking fuel trims reveals the following: STFT Bank1 & Bank2 stay on or around +- 9%. ( varies ) STFT B2 Sensor 2 stays at 99.2 all the time. Is this trul...
March 09, 2009
2001 Lexus RX300 3.0L MIL Lamp on VIN: JTJGF10U21
P0171: Lean Bank 1. ... while highway driving. P0171 and P0174. All checks ok now including + 5-10% fuel trims at 70 MPH. Both occasions, IAT was cold: 0 degrees F and 16 degrees F. There are no drivability concerns.
March 09, 2009
1999 Ford F-250 Super Duty XL 6.8L MIL Lamp on VIN: 1FTX21L3XE
P0171: bank one lean. I have smoke tested twice, check fuel pressure ok, checked pcv hose to back of intake tested mass air flow sensor according to bulletin, checks ok, will a bad MAF cause only po171 lean code, freeze frame is 1105 rpm, calc load 41.1%, coolant 204 degrees F, st ...
March 10, 2009
1999 Ford F-250 Super Duty XL 6.8L MIL Lamp on VIN: 1FTX21L3XE
P0171: bank one lean. I have smoke tested twice, check fuel pressure ok, checked pcv hose to back of intake tested mass air flow sensor according to bulletin, checks ok, will a bad MAF cause only po171 lean code, freeze frame is 1105 rpm, calc load 41.1%, coolant 204 degrees F, st ...
March 11, 2009
1999 Toyota 4Runner SR5 3.4L Hesitation, Misfire, MIL Lamp on VIN: JT3HN86R9X
P0171: Fuel System Too Lean (Bank 1). Hello there I have this 4 Runner with what seems to be a simple misfire issue. I have check plugs wires and coils and it still will misfire especially on #3. I have switched plugs wires and coils around and it still has a problem. It also has a no power when a...
March 11, 2009
2001 Toyota Corolla CE 1.8L Hesitation, Misfire, MIL Lamp on VIN: 1NXBR12E91
P0171: Fuel System Too Lean (Bank 1). ... shop with a p0171 .and p0300. My mastertech scaner shows at idle MAF 2.5 GR/s , both o2 sensors 0.00v ,stft 19%,ltft 29%. I have run fuel press ,compression,check for vac leaks and check injector resistance everything is i...
March 11, 2009
1996 Ford Taurus LX 3.0L MIL Lamp on VIN: 1FALP53S3T
P0171: system too lean bank 1. ... engine light on and 2 codes (P0171 & P0174) fuel trims Long Term were about 16% & 18%. Hooked up smoke machine and found 2 leaks, (one out of EGR gasket & other coming out of hose going to EVAP.) Fixed both of them and trim dropped down to abou...
March 12, 2009
2000 Ford Escort LX 2.0L MIL Lamp on VIN: 3FAFP13P41
P0171: lean bank1 code. ... ther driveability concerns. No stalling, poor idling or running. Fuel pressure ok, smoked for leaks at intake, checked for vac leak sources, none found. LTFT 25 at idle- normal operating temp. within normal range cold @idle. The P0731 code is intermittent....
March 12, 2009
1998 Oldsmobile Intrigue GL 3.8L MIL Lamp on VIN: 1G3WS52K3W
P0171: Fuel System Lean. THANKS IN ADVANCE I was blessed with this return work from another shop They had replaced lower intake gasket and upper intake manifild due to coolant leak Found lower intake bolts not properly torqued. removed upper and lower intake and replaced gaskets The v...
March 12, 2009
2003 Ford Windstar LX 3.8L MIL Lamp on VIN: 2FMZA50433
P0171: lean condition on bank 1. ... Ford windstar that keeps setting c.e. light with lean codes: p0171 and p0174= lean condition on both banks. We have done whatever necessary to pintpoint the source or cause of lean codes; but witout success. We have checked ...
March 13, 2009
2001 Toyota Corolla CE 1.8L Hesitation, Misfire, MIL Lamp on VIN: 1NXBR12E91
P0171: Fuel System Too Lean (Bank 1). ... shop with a p0171 .and p0300. My mastertech scaner shows at idle MAF 2.5 GR/s , both o2 sensors 0.00v ,stft 19%,ltft 29%. I have run fuel press ,compression,check for vac leaks and check injector resistance everything is i...
March 13, 2009
2002 Chevrolet Camaro 3.8L MIL Lamp on VIN: 2G1FP22K92
P0171: Fuel Trim System Lean (Bank 1). stB1-(+2%) ltB1-(+20%) stB2-(+5%) ltB2-(+20%) Couldn't locate any external vacuum leaks. There is a TSB on that condition about clogged injectors.
March 14, 2009
1999 Ford Contour SE 2.5L MIL Lamp on VIN: 1FAFP66L6X
Does anyone know if I can obtain the seals where the intake manifold runner control shaft goes into the lower intake manifold. I have a vacuum leak at these seals and the dealer says I have to buy the complete lower intake manifold assy. This is the shaft , on...
March 18, 2009
2002 Toyota Camry SE 2.4L Excessive Emissions, Misfire, MIL Lamp on VIN: 1GCCS1442T
P0171: Fuel System Too Lean (Bank 1). not to much exp on toyota 1 month ago customer brings in car has po442 decined looking into code,car run ok,now problem with idel and shows slight misfire,lean bk 1,dont know toyota to well,and would like to know what direction to take from you guys,fuel press...
March 20, 2009
2001 Volkswagen Golf GLS 2.0L MIL Lamp on VIN: 9BWGT21J61
P0171: bank 1 lean. ... repeat cust. for this concern.mil on p0171 code for bank 1 lean. cannot find vacuum lek. o2 sensors switch properly.light will shut off for few days then returns. inspected secondary air system.seems fine.sometimes will run rough in morning at first start ...
March 20, 2009
2001 Honda Accord EX 2.3L MIL Lamp on VIN: JHMCG665XX
P0171: Fuel System Too Lean (Bank 1). ... driveability symptoms. P1071 was a current code when vehicle came in and was initially tested, now has become a history code after a few road tests and a collision at the shop today. Dented fenders aside, fuel trim, ST 10-25%, LT 14-18%. Idle quality is go...
March 23, 2009
2003 Kia Spectra 1.8L No Start, Poor Idle Quality VIN: KNAFB12193
P0171: Fuel System Too Lean (Bank 1). cust complaint of dies driving and hard to restart and hard start after fueling road tested for dying did not duplicate problem customer says hard to start after every fill up i took vehicle to gas station and added fuel vehicle spins over will not start hold ...
March 23, 2009
2002 Toyota Camry SE 2.4L Excessive Emissions, Misfire, MIL Lamp on VIN: 1GCCS1442T
P0171: Fuel System Too Lean (Bank 1). not to much exp on toyota 1 month ago customer brings in car has po442 decined looking into code,car run ok,now problem with idel and shows slight misfire,lean bk 1,dont know toyota to well,and would like to know what direction to take from you guys,fuel press...
March 24, 2009
2005 Saturn Ion-1 2.2L lack of power VIN: 1G8AF54F15
P0171: Fuel System Lean. ... power. Customer stated that the car would idle good but bog down when the accelerator was pressed, and didn't have enough power to pull itself. Scanned and found the codes listed. I took it out for a test drive and the car ran perfect. Cleared codes and re...
March 25, 2009
2004 Volvo S60 2.4 2.4L Poor Idle Quality VIN: YV1RS61T64
P0171: lean mixture bank 1. Car came in with rolling idle, ck engine light, and whistling noise around #2 cyl on intake. Changed intake gskt. bolt torque was not even, but gskt looked ok. I am wondering if it is possible for the crankcase vent system to be at fault. If I pull the dipstic...
March 25, 2009
1999 Toyota Camry CE 2.2L Poor Idle Quality, Hesitation, Cuts out VIN: 4T1BG22K0X
P0171: Fuel System Too Lean (Bank 1). ... left B pillar.Disconnected battery, performed body repairs, hooked battery up no start. Checked plugs ( dry plugs ), checked spark ( good spark ), checked injector pulse ( good pulse ), checked fuel pump pressure ( only 8psi ), replaced fuel pump, engine s...
March 26, 2009
2001 Dodge Durango SLT 4.7L Poor Fuel Economy VIN: 1B4HS28N11
P0171: Fuel System Lean (Bank 1). this car has poor fuel mileage and blow black smoke at idle. i replaced upsteam and down stream and found power steering fluid in connectors and then looked and found power steering sensor leaking fluid. i replaced power steering sensor and clean all connector...
March 27, 2009
1999 Dodge Caravan SE 3.3L Excessive Emissions, MIL Lamp on, crank no start VIN: 2B4GP52G8X
P0171: Fuel System Lean (Bank 1). Here is the scoop on this caravan...At times on cold start the car will crank no start, at this time it has spark but will crank over and smells strong of fuel. The only way to get it to start is to hold your foot to the floor then of course it will run rough ...
March 29, 2009
1999 Buick Regal LS 3.8L Poor Fuel Economy, MIL Lamp on VIN: 2G4WB52K3X
P0171: Fuel System Lean. ... Initially it had a code for a mass air flow sensor code. Upon inspection of the sensor data it showed that the sensor was reading 3.88 gm/s at idle which is off from the minimum of 4 gm/s. Sensor was replaced and vehicle was fine for about 3 days. Code ret...
March 30, 2009
2005 Mercedes-Benz SLK350 3.5L Misfire VIN: WDBWK56F75
P0171: rt. bank mixture at limit at idle. Thanks as always fellow technicians Mil is on, all misfire codes and mixture codes for rt. bank of cylinders, If this was a M112 or M113 I'd be sending him to the dealer for warranty catalyst replacement on the rt. bank. I have only worked on a few of the M272...
March 30, 2009
2005 Mercedes-Benz SLK350 3.5L Misfire VIN: WDBWK56F75
P0171: rt. bank mixture at limit at idle. Thanks as always fellow technicians Mil is on, all misfire codes and mixture codes for rt. bank of cylinders, If this was a M112 or M113 I'd be sending him to the dealer for warranty catalyst replacement on the rt. bank. I have only worked on a few of the M272...
March 31, 2009